Impact of rapid pathogen detection in ICU patients with suspected pneumonia on antimicrobial therapy: randomized, controlled open-label feasibility trial (IRISPAT-1)

Background Evidence that multiplex polymerase chain reaction (mPCR) improves antimicrobial therapy and clinical outcomes in the critical care setting is limited. We assessed the impact of rapid mPCR on antibiotic therapy in mechanically ventilated critically ill patients with suspected pneumonia. Methods IRISPAT-1 was a single center, randomized, controlled open-label trial designed to determine the feasibility, safety, and potential impact of rapid respiratory pathogen detection on antibiotic therapy in mechanically ventilated critically ill patients with suspected pneumonia. Mechanically ventilated adults with suspected pneumonia and treated with new antibiotics within 24 h were randomized to standard care or mPCR using BioFire ® FilmArray ® Pneumonia Panel in addition to standard care (FA Pneumonia Panel group). Primary outcome was time interval (hours) to appropriate antimicrobial therapy. Results Forty mechanically ventilated patients with suspected pneumonia were randomized (20 = standard care, 20 = FA Pneumonia Panel) between July 7, 2024 and October 4, 2025. Median (IQR) time to appropriate antibiotic therapy was shorter in the FA Pneumonia Panel group compared to the standard care group (7 [5–16] vs. 72 [41–140] hours, HR 3.3; 95%CI [1.6, 6.6], p = 0.001). Adherence to treatment algorithm was observed in 90% (18/20) of patients in the FA Pneumonia Panel group. There were no differences in use of broad-spectrum antibiotics, duration of antibiotics, ventilator free days or vasopressor free days and 28-day mortality between treatment groups. Conclusion Rapid mPCR with high adherence to antibiotic algorithms shortened time to appropriate antibiotics compared to standard care in mechanically ventilated patients with suspected pneumonia. Trial registration Registered at clinicaltrials.gov (NCT06478953) on June 23, 2024.